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A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaNumber

These numbers are real multiples of i, whose square is −1.

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Your new ahaImaginary Numbers

Imaginary Numbers — value or symbol: i = √-1. Source: Imaginary number

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More from Numbers with Stories

A few more worth knowing.

  1. 12Named for Ronald Graham, this famously enormous number arose as an upper bound in a Ramsey-theory problem.RECALL
    Graham's Number

    Graham's number, once the largest number used in a serious proof, is too vast to write in ordinary notation.

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  2. 13Squaring either of these two values gives the same positive number.IDENTIFY
    Square Roots

    A square root reverses squaring, and every positive number carries both a positive and negative root.

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  3. 14These raised numbers indicate powers; positive integer values count repeated factors.RECALL
    Exponents

    Exponents represent repeated multiplication, growing numbers far faster than addition or plain multiplication.

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